U.S. Environmental Protection Agency (EPA) Announced Methods and Guidance for Evaluating Efficacy of Antimicrobial Products against Clostridium difficile Spores

On September 29, 2017, the U.S. Environmental Protection Agency (EPA) announced the availability of two final test method Standard Operating Procedures (SOP) for evaluating the efficacy of antimicrobial products against Clostridium difficile (C. diff) spores.

C. diff is an anaerobic, spore-forming bacterium and a leading hospital-acquired infection. The spores survive on hard surfaces such as glass, metals, and plastics that are commonly found in health-care settings.

Antimicrobial pesticides are used to reduce the number of spores on environmental surfaces. Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the registrant of an antimicrobial product with a public health claim is required to submit efficacy data to EPA in support of the product’s registration.

EPA MLB SOP MB-28 describes the test methodology for producing and storing standardized spore suspensions of C. diff based on ASTM E2839, Standard Test Method for Production of C. difficile Spores for Use in Efficacy Evaluation of Antimicrobial Agents (ASTM International). A spore suspension should be developed and qualified according to EPA MLB SOP MB-28 before an efficacy evaluation can be performed using method EPA MLB SOP MB-31. EPA MLB SOP MB-31 describes a quantitative method intended for evaluating the sporicidal efficacy of liquid disinfectants against spores of C. diff on inanimate, hard, non-porous surfaces.

EPA solicited comments on the clarity of the test method SOPs and the regulatory guidance in December 2016. EPA received comments from twelve entities and revised the drafts to incorporate suggested changes. EPA posted its response to those comments in Docket No. EPA-HQ-OPP-2016-0753-0026. EPA also is working with ASTM International, a standard-setting organization, on adoption of these test methods as official ASTM standards.

This website uses cookies to improve user experience. By using this website without changing the cookie settings in your web browser you consent to all cookies in accordance with the Cookie Policy. Our Cookie Policy